Locking chuck

ABSTRACT

A chuck for use with a manual or powered driver having a housing and a rotatable drive shaft extending therefrom is provided. The chuck includes a generally cylindrical body member having a nose section and a tail section. Each of a plurality of jaws is slidably positioned in one of a plurality of angularly disposed passageways in the body. Each jaw has a jaw face formed on one side thereof and threads formed on the opposite side thereof. A nut is rotatably mounted on the body in engagement with the jaw threads so that rotation of the nut moves the jaws axially within the passageways. A locking member, in a first axial position, is rotatable with respect to the driver housing. In a second axial position, it operatively engages the housing and the nut so that the locking member is rotationally held to the housing and the nut so that the nut is rotationally held to the housing. The locking member is axially reciprocal between the first axial position and the second axial position.

BACKGROUND OF THE INVENTION

The present invention relates generally to chucks for use with drills orwith electric or pneumatic power drivers. More particularly, the presentinvention relates to a chuck of the keyless type which may be tightenedor loosened by hand.

Both hand and electrical or pneumatic tool drivers are well known.Although twist drills are the most common tools on such drivers, thetools may also comprise screw drivers, nut drivers, burrs, mountedgrinding stones, and other cutting or abrading tools. Since the toolshank may be of varying diameter or of polygonal cross section, thedevice is usually provided with a chuck that is adjustable over arelatively wide range. The chuck may be attached to the driver by athreaded or tapered bore or any other suitable means.

A variety of chuck types have been developed that are actuated byrelative rotation between a chuck body and an annular nut. In a typicaloblique jawed chuck, for example, a body member includes threepassageways disposed approximately 120° apart from each other. Thepassageways are configured so that their center lines meet at a pointalong the chuck axis forward of the chuck body. Three jaws areconstrained by and movable in the passageways to grip a cylindrical toolshank disposed approximately along the chuck center axis. The nutrotates about the chuck's center and engages threads on the jaws so thatrotation of the nut moves the jaws in either direction in thepassageways. The body and nut are configured so that rotation of the nutin one direction (the closing direction) with respect to the body forcesthe jaws into gripping relationship with the tool shank, while rotationin the opposite direction (the opening direction) releases the grippingrelationship. Such a chuck may be keyless if it is rotated by hand.Examples of such chucks are disclosed in U.S. Pat. Nos. 5,125,673 and5,193,824, commonly assigned to the present assignee and the entiredisclosure of each of which is incorporated by reference herein. Variousconfigurations of keyless chucks are known in the art and are desirablefor a variety of applications.

Keyless chucks actuated by relative rotation between a nut and a chuckbody include means to control the rotational position of the nut and thebody. For example, a first sleeve may be provided in communication withthe nut while a second sleeve, which is independent of the first sleeve,may be attached to the body. Thus, a user may rotate the first sleevewith one hand while gripping the second sleeve with the other hand,thereby holding the body still. Alternatively, in some devices in whichonly a single sleeve is provided, a user may grip the single sleeve andactuate the tool driver to rotate the spindle, thereby rotating thechuck body with respect to the sleeve. In addition, a mechanism may belocated in a driver to lock the spindle of the driver when the driver isnot actuated, thus enabling use of a single sleeve chuck.

SUMMARY OF THE INVENTION

The present invention recognizes and addresses the foregoingconsiderations, and others, of prior art constructions and methods.

Accordingly, it is an object of the present invention to provide animproved chuck.

It is a further object of the present invention to provide an improveddrill.

It is a still further object of the present invention to provide a chuckhaving an improved mechanism for loosening and tightening the chuck.

These and other objects are achieved by a chuck for use with a manual orpowered driver having a housing and a rotatable drive shaft extendingtherefrom. The chuck includes a generally cylindrical body member havinga nose section and a tail section. The tail section is configured tomate with the drive shaft so that the body rotates with the drive shaft.The nose section has an axial bore formed therein and a plurality ofangularly disposed passageways formed therethrough and intersecting theaxial bore. Each of a plurality of jaws is slidably positioned in one ofthe annularly disposed passageways. Each of the jaws has a jaw faceformed on one side thereof and threads formed on the opposite sidethereof. A nut is rotatably mounted on the body in engagement with thethreads on the jaws so that rotation of the nut moves the jaws axiallywithin the passageways. A locking member is, in a first axial position,rotatable with respect to the driver housing. In a second axialposition, it operatively engages the housing and the nut so that thelocking member is rotationally held to the housing and to the nut sothat the nut is rotationally held to the housing. The locking member isaxially reciprocal between the first axial position and the second axialposition.

In another preferred embodiment, a chuck includes a generallycylindrical body member having a nose section and a tail section. Thetail section is configured to mate with the drive shaft so that the bodyrotates with the drive shaft. The nose section has an axial bore formedtherein and a plurality of angularly disposed passageways formedtherethrough and intersecting the axial bore. Each of a plurality ofjaws is slidably positioned in one of the angularly disposedpassageways. Each jaw has a jaw face formed on one side thereof andthreads formed on the opposite side thereof. A nut is rotatably mountedon the body in engagement with the threads on the jaws so that rotationof the nut moves the jaws axially within the passageways. The chuck alsoincludes an axially reciprocal sleeve and a clutch mechanism disposedoperatively between the body and the nut. The sleeve is rotationallyheld to, and axially movable with respect to, the clutch mechanism in atleast one axial position of the sleeve. The clutch mechanism and the nutinclude respective engaging surfaces disposed so that the clutchmechanism and the nut are rotationally held to each other when engagedby a rotational force applied at the engaging surfaces by at least oneof the clutch mechanism and the nut and so that the clutch mechanism isurged axially away from the nut upon application of the rotationalforce. A biasing mechanism is in operative communication with the clutchmechanism and opposes axial movement of the clutch mechanism away fromthe nut. The biasing mechanism is configured with the clutch mechanismto resist disengagement of the engaging surfaces until the rotationalforce exceeds a predetermined level.

Other objects, features and aspects of the present invention arediscussed in greater detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

A full an enabling disclosure of the present invention, including thebest mode thereof to one of ordinary skill in the art, is set forth moreparticularly in the remainder of the specification, which makesreference to the accompanying figures, in which;

FIG. 1 is a longitudinal view, partly in section, of a chuck inaccordance with an embodiment of the present invention;

FIG. 2 is a longitudinal view, partly in section, of the chuck as inFIG. 1;

FIG. 3 is a longitudinal view, partly in section, of the chuck as inFIG. 1;

FIG. 4 is an exploded view of the chuck as in FIG. 1;

FIG. 5 is a partial exploded view of a chuck in accordance with anembodiment of the present invention;

FIG. 6A is a longitudinal view, in cross section, of a chuck inaccordance with an embodiment of the present invention;

FIG. 6B is a longitudinal view, in cross section, of the chuck as inFIG. 6A;

FIG. 7A is a longitudinal view, in cross section, of a chuck inaccordance with an embodiment of the present invention;

FIG. 7B is a longitudinal view, in cross section of the chuck as in FIG.7A;

FIG. 8A is a longitudinal view, in cross section, of a chuck inaccordance with an embodiment of the present invention;

FIG. 8B is a longitudinal view, in cross section, of the chuck as in FIG8A; and

FIG. 9 is an exploded view of the chuck as in FIGS. 6A and 6B.

Repeat use of reference characters in the present specification anddrawings is intended to represent the same or analogous features orelements of the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Reference will now be made in detail to presently preferred embodimentsof the invention, one or more examples of which are illustrated in theaccompanying drawings. Each example is provided by way of explanation ofthe invention, not limitation of the invention. In fact, it will beapparent to those skilled in the art that modifications and variationscan be made in the present invention without departing from the scope orspirit thereof. For instance, features illustrated or described as partof one embodiment may be used on another embodiment to yield a stillfurther embodiment. Thus, it is intended that the present inventioncovers such modifications and variations as come within the scope of theappended claims and their equivalents.

In the embodiments illustrated in the figures, a drill chuck has a bodyconfigured for attachment to a drill spindle and having passages inwhich jaws are held. The jaws reciprocally move (in either an opening orclosing direction) by a threadedly engaged nut. In these embodiments, alocking member in the form of a generally cylindrical sleeve is axiallymoveable to either of two positions. In the first position, the sleeverotates with respect to the drill housing. In the second position, it isrotationally held to the housing and to the nut. That is, the lockingsleeve does not rotate with respect to the housing or to the nut. In theembodiment shown in FIGS. 1-4, the locking sleeve remains in the secondposition throughout opening and closing of the chuck once the operatormoves the locking sleeve into the appropriate position. In theembodiments shown in FIGS. 6A-9, however, the locking sleeve is held tothe nut through a clutch mechanism that rotationally locks the sleeveand housing to the nut as long the clutch mechanism or nut does notsubstantially resist the rotational torque applied by the othercomponent, as is described in more detail below. When the resistancedoes overcome this torque, the nut teeth and clutch teeth slip over eachother, allowing the nut to rotate with the body with respect to thelocking sleeve, thereby preventing over tightening. It should beunderstood, however, that the present invention is not limited to suchembodiments.

Referring to FIGS. 1-4, a chuck 10 includes a front sleeve 12, a body14, jaws 16 and a nut 18. Body 14 is generally cylindrical in shape andcomprises a nose or forward section 20 and a tail or rearward section22. An axial bore 24 is formed in nose section 20. Axial bore 24 isdimensioned somewhat larger than the largest tool shank that the chuckis designed to accommodate. A threaded bore 26 is formed in tail section22 and is of a standard size to mate with a drive shaft 28 of a poweredor hand driver indicated in part at 30. The bores 24 and 26 maycommunicate at a central region of body 14. While a threaded bore 26 isillustrated, such bore could be replaced with a tapered bore of astandard size to mate with a tapered drive shalf or with any othersuitable connection mechnanism.

Passageways 32 are formed in body 14 to accommodate each jaw 16. Threejaws 16 are employed, and each jaw is separated from the adjacent jaw byan arc of approximately 120°. The axes of the passageways 32 and thejaws 16 are angled with respect to the chuck axis and intersect thechuck axis at a common point ahead of chuck body 14. Each jaw 16 has atool engaging portion 34, which is generally parallel to the axis ofchuck body 14, and threads 36 on its opposite or outer surface. Threads36 may be constructed in any suitable type and pitch.

Body 14 includes a thrust ring member 38 which, in a preferredembodiment, may be integral with the body. In an alternate embodiment,thrust ring 38 may be a separate component from the body member. Thrustring 38 may also include a ledge portion to receive a bearing assembly40. Thrust ring 38 includes a plurality of jaw guideways 42 formedaround its circumference to permit retraction of the jaws 16therethrough.

Nut 18 is a one piece nut which includes threads 44 for mating withthreads 36 on jaws 16. Nut 18 is positioned about the body in engagementwith the jaw threads so that when the nut is rotated with respect tobody 14, the jaws will be advanced or retracted. A nut retainer 46 ispressed to nose section 20 of body 14 and engages nut 18 at a forwardledge 48 thereof. Thus, retainer 46 secures nut 18 in the axialdirection with respect to the body.

Nut 18 also includes a plurality of notches 50 receiving drive dogs 52of front sleeve 12 by which front sleeve 12 and nut 18 are rotationallyheld to each other. A nose piece 54 is pressed to forward section 20 ofbody 14 and retains front sleeve 12 in the axially forward direction byan annular lip 56 of sleeve 12.

The outer circumferential surface of sleeve 12 may be knurled or may beprovided with longitudinal ribs or any other configuration to enable auser to grip it securely. The sleeve may be fabricated from a structuralplastic such as polycarbonate, a filled polypropylene, for example glassfilled plypropylene, or a blend of structural plastic materials. Othercomposite materials such as, for example, graphite filled polymerics mayalso be suitable in a given environment. In one embodiment, the sleeveis constructed from a 30% glass filled nylon 66 material. As would beappreciated by one skilled in the art, the materials for which the chuckof the present invention is fabricated will depend on the end use of thechuck, and the above are provided by way of example only.

A pair of rear body flanges 58 and 60 are pressed to rear portion 22 ofbody 14 at knurled portion 62. An O-ring 64 sits in an annular shoulder66 of rear body flange 60 to limit axial movement of a rear sleeve 68 inboth the forward and rearward directions as is discussed below. Althoughrear body flanges 58 and 60 are illustrated in this embodiment asseparate members from body 14 it should be understood that they may beconstructed integrally therewith.

Rear sleeve 68 is axially reciprocal with respect to body 14. In theposition of rear sleeve 68 shown in FIG. 1, axially aligned teeth 70extending radially inward from an inner circumferential surface 72 ofrear sleeve 68 engage axially aligned teeth 74 (referring also to FIG.4) extending radially outward from outer circumferential surface 76 ofrear body flange 58. Thus, rear sleeve 68 is rotationally held to body14 through rear body flange 58. O-ring 64 and rear body flange 60prevent further rearward axial movement of rear sleeve 68. Using thisaxial rear sleeve position, an operator may operate chuck 10 as atwo-sleeve keyless chuck. By gripping rear sleeve 68 and front sleeve12, the operator holds body 14 and nut 18, respectively. Rotating thesleeves with respect to each other rotates the body and nut with respectto each other, thereby opening or closing the chuck depending upon thedirection of relative rotation.

As shown in FIG. 2, however, forward axial movement of rear sleeve 68disengages teeth 70 from teeth 74, and teeth 70 move toward axiallyaligned teeth 78 extending radially outward from an outercircumferential surface 80 of front sleeve 12. Teeth 78 are disposed farenough forward of teeth 74 so that teeth 70 clear teeth 74 beforeengaging teeth 78. This allows for any slight rotation of sleeve 68necessary to align teeth 70 with the gaps between teeth 78. It should beunderstood, however, that teeth 78 may be disposed more closely to teeth74 so that teeth 70 engage teeth 78 before entirely disengaging teeth74.

As teeth 70 engage teeth 78, axially aligned teeth 82, which extendradially inward from inner circumferential surface 84 of rear sleeve 68,engage axially aligned teeth 86, which extend radially outward from anouter circumferential surface 88 of drill housing 90. Referring to FIGS.3 and 4, in the rear sleeve's axially forward position, rear sleeveteeth 82 and 70 engage teeth 86 and teeth 78 of drill housing 90 andfront sleeve 12, respectively. Further forward axial movement of rearsleeve 68 is prevented by O-ring 64, upon which bears shoulder 92 ofrear sleeve 68. In this position, teeth 70 have completely disengagedteeth 74 of rear body flange 58.

Accordingly, in the rear sleeve axial position shown in FIG. 3, nut 18is rotationally held to housing 90 by front sleeve 12 and rear sleeve68. At the same time, nut 18, front sleeve 12 and rear sleeve 68 arerotatable with respect to body 14, which rotates with spindle 28.Accordingly, activation of drill 30 to rotate spindle 28 rotates body 14with respect to nut 18, thereby opening or closing chuck 10 dependingupon the spindle's rotational direction. Because opening and closing ofthe chuck with sleeve 68 in this position requires only one of theoperator's hands (to operate the drill), the operator may use his otherhand to hold a drill bit or other tool being locked into or releasedfrom the chuck.

Rear sleeve 68 may have the same or similar construction as front sleeve12.

It should be understood that various suitable locking mechanisms may beused to rotationally hold the rear sleeve to the body, the front sleeve,the housing and/or any other chuck component as appropriate in a givenembodiment of the present invention. For example, the teeth 86 asillustrated in FIG. 5 are wider and more spaced apart than the teeth 86illustrated in FIG. 4. Correspondingly, teeth 82 at the rear of rearsleeve 68 are wider to fill the gaps between teeth 86. In furtherembodiments, discussed in more detail below, radially extending teethmay be replaced by axially extending teeth. Moreover, it should beunderstood that any suitable locking mechanism construction andconfiguration is within the scope and spirit of the present invention.

In the embodiment illustrated in FIGS. 6A, 6B and 9, front sleeve 12 ispressed onto a nose piece 100 at 102. Nose piece 100 is, in turn,pressed onto forward section 20 of body 14. Accordingly, unlike theembodiment illustrated in FIGS. 1-4, front sleeve 12 is rotationallyheld to body 14 rather than nut 18.

Rear sleeve 68 is rotationally held to nut 18 during normal operationthrough a clutch mechanism including an annular clutch plate 104.Axially aligned teeth 106 extend radially outward from an outercircumferential surface 108 of clutch plate 104 and are received bygrooves 110 between axially aligned teeth 112 extending radially inwardfrom an inner circumferential surface of a forward section 114 of rearsleeve 68. Rear sleeve 68 is axially reciprocal with respect to clutchplate 104 by the interaction between teeth 106 and grooves 110.

Clutch plate 104 is held in position between body 14 and nut 18 by awave spring 116. Wave spring 116 bears on one side on body 14 throughnose piece 100 and on the other side directly on clutch plate 104. Wavespring 116, which may include one or more individual springs, biasesclutch plate 104 axially toward nut 18. A lubricant may be provided onone or both sides of wave spring 116 and/or one or both surfaces ofclutch ring 104 and nose piece 100 to facilitate relative rotationbetween the clutch plate and the nose piece.

An engaging surface of clutch plate 104 includes a pair of lugs 117extending axially forward from annular surface 118 of the engagingsurface. Sides 120 of each lug 117 are disposed at an oblique angle withrespect to a plane 122 including the chuck axis 124.

One side 120 of each lug 117 abuts an opposing side 126 of a lug 128extending axially from an annular surface 130 of an engaging surface ofnut 18 as nut 18 is rotated with respect to body 14. As with sides 120,sides 126 are disposed at an oblique angle with respect to plane 122.

Rear sleeve 68 is biased forwardly by a wave spring 132, here formed bya plurality of wave springs, bearing on one side on body 14 through arear body plate 134 pressed onto body 14 at 136 and on the other side onrear sleeve 68 through a rear sleeve flange 138. Although notillustrated in FIG. 9, it should be understood that surface 136 may beknurled to facilitate the press fit between it and rear body plate 134.Furthermore, while rear sleeve flange 138 is illustrated as beingattached to rear sleeve 68 by dowels 140, it should be understood thatany suitable attachment mechanism may be employed. For example, the rearsleeve flange may be integral with the rear sleeve or may be a separatepiece integrally molded with the rear sleeve. One or both sides ofspring 132 and/or one or both of the sides of rear body plate 134 andrear sleeve flange 138 on which it directly bears may include a suitablelubricant to facilitate relative rotation between sleeve 68 and body 14.

In its axial position illustrated in FIG. 6A, rear sleeve 68 isrotatable with respect to body 14, and chuck 10 may be operated as atwo-sleeve keyless chuck. For example, an operator may grip front sleeve12 to rotationally secure body 14 and may grip rear sleeve 68 torotationally secure nut 18, which is rotationally held to sleeve 68through clutch ring 104 and the interface between lugs 117 and 128.Thus, relative rotation between front sleeve 12 and rear sleeve 68 opensor closes chuck 10 depending upon the direction of relative rotation.

When chuck 10 reaches a fully opened or a fully closed position, furthermovement of jaws 16 is prevented by the abutment of face 142 of jaws 16against nut 18 or by the abutment of jaw faces 34 against each other ora tool. Nut 18 then tightens onto threads 36 of jaws 16 and resistsfurther rotation.

Because of the angled interface between sides 126 and 120 of lugs 128and 117, respectively, part of the rotational force applied by sleeve 68to nut 18 through clutch ring 104 is translated to an axial forcetending to separate the clutch ring and the nut. During normaloperation, this force is resisted by the bias of spring 116. Because nut18 is tightened onto the jaw threads as chuck 10 reaches a fully openedor closed position, however, nut 18 resists the rotational force appliedby the clutch plate, and additional rotational force is required tofurther rotate the nut. When the force applied between sides 126 and 120creates a separation force exceeding the counter force provided bybiasing spring 116, clutch plate 104 is moved axially forward,compressing spring 116. Lugs 117 and 128 thus ride over one another,thereby allowing sleeve 68 to rotate with respect to nut 18 andpreventing over tightening of the nut.

The force necessary to cause clutch plate 104 to ride over nut 18 isprimarily determined by the strength of spring 116 and the angle of thesides 126 and 120. In one preferred embodiment, spring 116 includes two22 lb wave springs, and sides 120 and 126 are disposed at an angle ofapproximately 60° from surfaces 118 and 130, respectively. It should beunderstood, however, that the construction and dimensions of thesecomponents may be varied as suitable for a given chuck construction.

The chuck illustrated in FIGS. 6A, 6B and 9 may also be opened andclosed through operation of the drill spindle. Accordingly, referring toFIGS. 6B and 9, rear sleeve 68 may be pushed axially rearward againstthe bias of spring 132 so that axially aligned teeth 144 extendingradially inward from inner circumferential surface 146 of rear sleeve 68engage axially aligned teeth 148 extending radially outward from anouter circumferential surface of drill housing 90. Rear sleeve 68 slidesaxially rearward with respect to clutch plate 104 but remainsrotationally held thereto through the cooperation of grooves 110 andteeth 106. Thus, nut 18 is rotationally held to housing 90 throughclutch plate 104 and rear sleeve 68. While holding sleeve 68 in theaxially rearward position illustrated in FIG. 6B, an operator mayactivate the drill to rotate spindle 28, thereby rotating body 14 withrespect to nut 18 to open or close chuck 10 depending on the spindle'srotational direction. The clutch mechanism operates as discussed abovewith respect to FIG. 6A to prevent over tightening, except thatrotational force is applied through nut 18 rather than through clutchplate 104.

The embodiment illustrated in FIGS. 7A and 7B operate similarly to theembodiment illustrated in FIG. 6A and FIG. 6B, primarily except for therotational engagement between rear sleeve 68 and housing 90. Forpurposes of clarity, wave spring 132 (FIGS. 6A and 6B) is notillustrated in FIGS. 7A and 7B. It should be understood, however, thatthis spring is present in the embodiment illustrated in FIGS. 7A and 7Bto perform a function similar to that discussed above. For example, thespring biases rear sleeve 68 forward to the axial position shown in FIG.7A.

Rather than employing radially extending teeth, rear sleeve flange 138includes radially aligned teeth 150 extending axially rearward from rearsleeve flange 138. A housing plate 152 includes radially aligned teeth154 extending axially forward therefrom and opposing teeth 150. In theaxial position illustrated in FIG. 7A, rear sleeve 68 is rotatable withrespect to body 14 and housing 90, and chuck 10 may be operated as atwo-sleeve keyless chuck as described above with respect to FIG. 6A.

As shown in FIG. 7B, rear sleeve 68 may be pulled rearwardly against thebiasing spring to engage teeth 150 and 154, thereby rotationally holdingsleeve 68 to housing 90. Sleeve 68 slides rearwardly with respect to,but remains rationally held to, clutch plate 104. Thus, nut 18 isrotationally held to housing 90 through clutch plate 104 and rear sleeve68. Activation of the drill to rotate spindle 28 thus rotates body 14with respect to nut 18, thereby opening or closing chuck 10 dependingupon the spindle's rotational direction.

The embodiment of chuck 10 illustrated in FIGS. 8A and 8B is constructedand operates similarly to the embodiment illustrated in FIGS. 7A and 7B,primarily except that the rear biasing spring 132 (FIGS. 6A and 6B) andrear body plate are replaced by a detent mechanism including a coilspring 156 and a ball 158. In one preferred embodiment, the detentmechanism is a self-contained mechanism that threads into body 14. Acollar or other suitable stop is provided to prevent ball 158 from beingpushed entirely out of the mechanism by spring 156.

Referring to FIG. 8A, rear sleeve 68 is held in the forward axialposition by ball 158 bearing against rear sleeve flange 138. With rearsleeve 68 in this position, chuck 10 may be operated as a two-sleevekeyless chuck as described above with respect to FIGS. 6A and 7A.

When rear sleeve 68 is pulled rearwardly, rear sleeve flange 138 pressesball 158 downward, compressing spring 156. If sufficient rearward axialforce is applied, rear sleeve 68 passes over ball 158 so that teeth 154engage teeth 150 to rotationally hold rear sleeve 68 to housing 90,thereby rotationally holding nut 18 to housing 90 through clutch plate104 and rear sleeve 68. Chuck 10 may then be opened or closed throughactivation of the drill as discussed above with respect to FIGS. 6B and7B, except that it is not necessary for the operator to grip rear sleeve68 during this operation. The rear sleeve is retained in the rearwardaxial position as shown in FIG. 8B by ball 158 bearing upon rear sleeveflange 138. Spring 156 is strong enough to hold rear sleeve 68 in therearward axial position as shown in FIG. 8B during opening and closingof chuck 10 but yet compressible enough so that an operator may moverear sleeve 68 between the forward and rearward axial positions.

While one or more preferred embodiments of the present invention aredescribed above, it should be appreciated that various suitableembodiments are encompassed by the present invention. For instance, inanother preferred embodiment, the reciprocal locking sleeve is mountedabout the chuck body and is axially movable to either of two operativepositions. In the first, the locking sleeve is rotationally held to thebody by opposing teeth on the sleeve and the body as at 70 and 74 inFIGS. 1 and 4 above. With the locking sleeve in this axial position, thechuck may be operated as a two-sleeve keyless chuck by relative rotationbetween the locking sleeve and a second sleeve rotationally held to thenut. The second sleeve may be forward of the locking sleeve. A suitablebiasing mechanism may be provided to bias the locking sleeve to thefirst axial position.

In this axial position, the locking sleeve does not rotatably engage thenut and is therefore rotatable with respect to the nut. Opposing lugs,such as lugs 117 and 128 on clutch plate 104 and nut 18 in FIG. 9, areprovided on the nut and the locking sleeve so that when the lockingsleeve is moved axially into engagement with the nut, the locking sleeveis rotationally held to the nut. While an operator grips the lockingsleeve, activation of the drill to rotate the drill spindle opens orcloses the chuck depending upon the rotational direction of the spindle.The lugs on the locking sleeve and nut have angled sides as describedabove with respect to the lugs on the clutch plate and nut in FIGS. 6Aand 6B, creating a clutch to prevent over tightening of the nut.

The clutching action causes the locking sleeve to move axially away fromthe nut. Thus, enough space is provided so that the locking mechanismbetween the locking sleeve and the body in the first axial position doesnot reengage during the clutching action. A clutch spring may beprovided between the nut and the body so that the nut moves away fromthe locking sleeve, with respect to the body, when the nut and lockingsleeve are pushed apart.

In a still further embodiment, the locking sleeve as described withrespect to the previous embodiment is always rotationally held to thedrill housing during the chuck's operation. The sleeve may be held inany suitable manner, for example by an axially toothed interface, sothat the locking sleeve may move axially, but not rotationally, withrespect to the drill housing. A spring bears on one end on the chuckbody and on its other end against the locking sleeve to bias the lockingsleeve away from the nut. Thus, during normal operation, the lockingsleeve does not engage the nut. To open or close the chuck, an operatoraxially moves the locking sleeve against the spring bias to engage thenut. As above, opposing angled teeth are provided on the nut and thelocking sleeve to rotationally hold them to each other. When the drillis thereafter activated to rotate the spindle, the body rotates withrespect to the nut, thereby opening or closing the chuck depending onthe spindle's rotational direction. When the chuck is fully opened orclosed, the nut and locking sleeve are pushed apart with respect to eachother, allowing the nut to again rotate with the body and therebypreventing over tightening. A clutch spring is provided between the nutand the body so that the nut moves away from the locking sleeve, withrespect to the chuck body, when the nut and locking sleeve are pushedapart, thereby reducing the axial force applied to the locking sleeveopposing the operator's grip.

Furthermore, it should be understood that the identification of a “rear”sleeve in the embodiments in the Figures is for illustrative purposesonly. Moreover, it should be understood by those skilled in this artthat the chuck components described above may be arranged and configuredin various suitable manners within the present invention. For example,the locking and biasing mechanisms may be arranged so that the lockingsleeve is pushed forward, rather than rearward to hold the nut to thedrill housing. Thus, various modifications and variations to the presentinvention may be practiced by those of ordinary skill in the art withoutdeparting from the spirit and scope of the present invention, which ismore particularly set forth in the appended claims. In addition, itshould be understood that aspects of the various embodiments may beinterchanged both in whole or in part. Furthermore, those of ordinaryskill in the art will appreciate that the foregoing description isprovided by way of example only, and is not intended to be limitative ofthe invention so further described in such appended claims.

1. A power driver comprising: a. a housing; b. a rotatable drive shaftextending therefrom; and c. a chuck, said chuck comprising, a generallycylindrical body having a nose section and a tail section configured torotate with said drive shaft, said nose section having an axial boreformed therein and a plurality of angularly disposed passageways formedtherethrough and intersecting said axial bore; a plurality of jawsslidably positioned in each of said angularly disposed passageways, eachof said jaws having a jaw face formed on one side thereof and threadsformed on the opposite side thereof; a nut rotatably mounted on saidbody in engagement with said threads on said jaws so that rotation ofsaid nut moves said jaws axially within said passageways; a firstgenerally cylindrical sleeve having an inwardly depending annular lip,said first sleeve being disposed about said nose section of saidcylindrical body, said first sleeve being rotationally fixed to said nutand axially fixed with respect to said body; a second generallycylindrical sleeve disposed about said body and over a portion of saidfirst sleeve, which in a first state is rotatable with respect to saidhousing and rotationally fixed to said body and in a second state isrotationally fixed to said housing and said first sleeve; a nutretaining member pressed to said nose section of said body and having anut contact portion for retaining said nut in its operative position;and a nosepiece having a first sleeve contact portion fixed on said nosesection of said body for axially retaining said first sleeve in saidoperative position, wherein said annular lip of said first sleeve isreceived between said nut retaining member and said first sleeve contactportion of said nosepiece.
 2. The power driver as in claim 1, whereinsaid second sleeve moves axially reciprocally with respect to said firstsleeve and said body.
 3. The power driver as in claim 2, said chuckfurther including a first locking mechanism disposed on said secondsleeve for rotationally locking said second sleeve to said housing insaid second state.
 4. The power driver as in claim 3, said chuck furtherincluding a second locking mechanism disposed on said second sleeve forrotationally locking said second sleeve to said body in said firststate.
 5. The power driver as in claim 4, said chuck further including athird locking mechanism disposed on said second sleeve for rotationallylocking said second sleeve to said nut in said second state.
 6. Thepower driver as in claim 5, said chuck further including a first annularflange coupled to said tail section of said body.
 7. The power driver asin claim 6, wherein said first annular flange is integrally formed withsaid tail section of said body.
 8. The power driver as in claim 6, saidchuck further including a stop disposed about an outer circumference ofsaid first annular flange so as to limit axial movement of said secondsleeve between said first and said second state.
 9. The power driver asin claim 8, said second sleeve being adapted to receive said stop. 10.The power driver as in claim 5, said chuck further including a secondannular flange, wherein said second annular flange defines radiallyoutward extending teeth for engaging said second locking mechanism onsaid second sleeve.
 11. The power driver as in claim 10, said firstlocking mechanism including a first plurality of axially aligned teethextending radially inward from an inner circumferential surface of saidsecond sleeve, wherein said housing includes axially aligned teethextending radially outward from an outer circumferential surface of saidhousing, and wherein in said second state said first plurality of saidsecond sleeve teeth engage said housing teeth to rotationally fix saidsecond sleeve to said housing.
 12. The power driver as in claim 11, saidsecond locking mechanism including a second plurality of axially alignedteeth extending radially inward from said inner circumferential surfaceof said second sleeve, wherein in said first state said second pluralityof said second sleeve teeth engage said second annular flange teeth torotationally fix said second sleeve to said body.
 13. The power driveras in claim 12, said third locking mechanism including a third pluralityof axially aligned teeth extending radially inward from said innercircumferential surface of said second sleeve, wherein said first sleeveincludes axially aligned teeth extending radially outward from an outercircumferential surface of said first sleeve, and wherein in said secondstate said third plurality of said second sleeve teeth engage said firstsleeve teeth to rotationally fix said second sleeve to said nut.
 14. Thepower driver as in claim 13, said chuck further including a detentdisposed on said body in communication with said second sleeve so thatsaid detent retains said second sleeve in either of said first state andsaid second state.
 15. The power driver as in claim 13, wherein saidfirst sleeve and said second sleeve include a gripping surface on theirouter circumference.
 16. The power driver as in claim 1, said chuckfurther including a bearing disposed between said body and said nut. 17.The power driver as in claim 1, said nut further comprising a one piecenut.